Exploring the association between microscopic colitis and celiac disease: A comprehensive analysis using the national in-patient data (2016-2019).

Background: Several investigations suggested correlation between microscopic colitis (MC) and celiac disease (CD). This study aimed to examine this relationship using large-sized, population-based data with adequate control for confounding factors.

Methods: This study employed the National Inpatient Sample (NIS) database over 4 years (2016-2019). Patients with/without MC in the presence/absence of CD were identified through ICD-10 codes. Univariate and multi-variate analyses involving odds ratios (OR) and 95% confidence intervals (CI) were performed.

Results: Overall, 26,836,118 patients were analyzed. Of whom, 6,836 patients had MC (n = 179 with CD and n = 6,657 without CD). The mean hospital stay was not significantly different between both groups (5.42 ± 5.44 days vs. 4.95 ± 4.66 days, P = 0.202). The univariate analysis revealed a significant association between MC and CD (OR = 22.69, 95% [19.55, 26.33], P < 0.0001). In the multi-variate analysis, which adjusted for potential confounders including age, race, hospital region, hospital teaching status, ZIP income, smoking status, alcohol overuse, hypertension, diabetes mellitus, lipidemia-related disorders, non-steroidal anti-inflammatory drug use, and selected auto-immune diseases, the association remained significant (OR = 15.71, 95% CI [13.52, 18.25], P < 0.0001). Moreover, in patients with MC, the presence of CD emerged as a significant, independent variable of in-hospital mortality in univariate (OR = 2.87, 95% [1.14, 7.21], P = 0.025) and multi-variate (OR = 3.37, 95% CI [1.32, 8.60], P = 0.011) analyses.

Conclusion: This study establishes a probable link between MC and CD, backed by both univariate and multi-variate analyses, while also identifying CD as an independent risk factor for increased mortality among MC patients. These findings need to be validated in real-world clinical studies.